Fire extinguisher



Jan? 1941.v G. E. FERGUSON 2 ,395

FIRE EXTINGUISHER I Filed Nov. 1, 1958 2 Sheets-Shea 1:

Af'ToRNEY J 7, 1941- G. E. FERGUSON 2,227,895

FIRE EXTINGUISHER Filed Nov; 1,1958 2 Sheets-Sheet 2 Flt-7.2. FIGB.

FIGS.

INVENTOR Patented Jan. 7, 1941 UNITED STATES FIRE EXTINGUISHER George Ennis Ferguson, Spring Valley, N. Y., as-

signor to Pyrene-Manufacturing Company,

Newark, N. J.,

a corporation of Delaware Application November 1, 1938, Serial No. 238,159

5 Claims.

This invention relates to apparatus for producing fire extinguishing foam by reaction of chemical solutions and more particularly to a fire extinguisher which may be regulated to vary the fiow of foam and the consistency of the foam discharged from the extinguisher.

In the use of fire extinguishers designed to produce foam by reaction of two chemical solutions separately stored in the extinguisher, it is frequently desirable to restrict the range of ejection so that the force of the foam striking an inflammable liquid, such as fuel oil, may be applied over the surface of the burning liquid without spattering. The effective use of foam under such conditions requires the flowing of a thick blanket of foam over the burning oil or other liquid to smother the fire and prevent re-ignition. Such a short range of ejection is particularly desirable on board a ship, in small engine rooms, and in other places where the burning is more or less confined and where sloppage of the foam and spattering of a burning liquid are to be avoided.

The restriction of the how of foam from such an extinguisher, by reason of the slower rate of reaction of chemicals, also varies the character of the foam and increases the total volume of foam that may be discharged using a given amount of chemicals. The total time required for completely discharging the extinguisher is, of course, also increased.

It is an object of my invention to provide apparatus for producing fire extinguishing foam by chemical reaction and discharging said foam in a smooth, non-pulsating stream, in which the character, volume, rate, force and total time of discharge of the foam may be varied. In addition, my apparatus makes it possible todischarge only a part of the contents of the fire extinguisher at one time, making it practical to retain the balance of the contents for any future emergency.

Another object of the invention is to provide apparatus for accomplishing the foregoing purposes, Which is a simple and practical construction, easy for an unskilled person to operate and easy to re-charge.

Another object of my invention is to provide a fire extinguisher for producing chemical foam which may be easily adjusted to discharge a predetermined maximum volume and rate of flow of foam so that too rapid an ejection of foam in the hands of an unskilled operator is impossible.

A further object of the invention is to provide a three chamber fire extinguisher having a re stricted flow of both reacting chemicals from two storage chambers into a mixing chamber, together with a metering stopple for effecting regulation of the flow of one of the solutions by the operator Without producing pulsations in the foam stream.

Other objects and advantages will be apparent from the following description of the fire extinguisher and the two forms of metering stopple shown in the drawings.

Figure l is a vertical sectional view through approximately the center of the upper end of a fire extinguisher in accordance with my invention, showing the metering stopple in elevation.

Figure 2 is a detailed sectional view of the metering stopple shown in Fig. 1, taken approximately through the center of the stopple.

Figure 3 is a bottom plan view of the metering stopple shown in Fig. 2.

Figure 4 is a side elevation of a modified form of metering stopple.

Figure 5 is a bottom plan view of the metering stopple shown in Fig. 4.

The fire extinguisher illustrating my invention comprises an outer cylindrical shell ID suitably closed at its lower end (not shown) and havin welded or otherwise fixed thereto a top member Ii provided with a central charging opening I2 and external threads I3 to receive the screwon cover M. This fire extinguisher may be adapted to be carried and inverted by hand, or, if sufficiently large, trunnions and/ or wheels may be provided to support the extinguisher as is well understood in the art. Welded or otherwise fixed to the interior of the shell H] a short distance below the top member H, is an annular partition iii-having a central circular opening IE to receive the cylinder H which forms the inner storage chamber 58 for one of the solutions. The cylinder ll preferably fits loosely in the opening i 6, leaving an annular opening of a fixed area through which the other solution stored in the space between the shell l0 and the cylinder 1?, or annular storage chamber 19, may flow into the mixing chamber 42. Cylinder Il may have a suitable cage 20 secured thereto provided with an annular flange 2i fitting tightly into the top of the cylinder ll and an integral top 20a in the shape of a truncated cone. The cage 2|] is also provided above this top portion with an annular collar 22 integrally connected to the main casting 2i! by the spaced webs 23. Collar 22 is proportioned to fit snugly within the opening l2 and in this manner retains the upper end of cylinder I! in a fixed position within the fire extinguisher. The lower end of cylinder I! may be held in place within the shell ID in any suitable manner (not shown). The screw-on cap I4 may be provided with a safety valve 24 of any conventional construction for use in case dangerous pressures are developed inside the fire extinguisher. The cap I4 is also provided with an outwardly extending flange which may be grasped for removing the top and internal threads 25 to engage the threads I3. A suitable rubber washer 26 is preferably seated in the cap so that it is compressed against the upper rim of the extinguisher when the cap is in place. Pressure release openings 21 are preferably also provided so that residual pressure in the fire extinguisher after it has been discharged will be relieved through the openings 2'! before the cap I4 has been completely unscrewed.

Centrally located in the cap is a threaded opening 28 through which the threaded rod 29 is passed. A suitable hand wheel 39 may be secured to the outer end of this rod outside of the fire extinguisher by means of the nut 3|. A short distance inside the cap I4, rod 29 is provided with a flange 32 and may carry a suitable rubber washer 33. The lower end of rod 29 is provided with a head 34 adapted to be held in swiveling relation to the stopple head 35 by means of the pins 36.

The stopple head 35, as shown more particularly in Figs. 2 and 3, may have clamped thereto a downwardly depending hollow cylindrical skirt 31 by means of the bolts 33. The bolts 38 preferably also hold in place a rubber disc or washer member 39 extending a substantial distance beyond the outer edge on skirt 31, together with a metal disc or washer 40 to hold the rubber disc 39 in place. Individual annular washers 4I may be interposed between the lugs 31a of the skirt member 3'! and the metal washer 40 to space the top skirt member 31 a predetermined distance from the disc 40. A circumferential opening is thus left between the upper edge of the skirt member 31 and metal washer 49 which may be made of any predetermined size, depending upon the thickness of the washers 4| that are employed. The skirt member 31 is proportioned to slide snugly through the opening M in the top portion 29a of the cage 28. The stopple head 35, skirt member 31 and the other parts clamped between these two members may be raised or lowered as a unit by rotation of the hand wheel 39 from outside of the fire extinguisher.

It will be seen that a mixing chamber 42 is provided above the partition I5 and foam may be discharged from the mixing chamber 42 through a suitable coupling member 43 secured in an opening in the top II by means of the nut 44. A flexible hose 45 or other discharge device may be removably connected to the coupling 43 by means of the connection 45. Coupling 43 is preferably provided with a screen 41 projecting into the mixing chamber 42 and having a number of perforations 48 through which the foam must pass in going from the mixing chamber 42 to the hose 45.

In the operation of this fire extinguisher, the storage chamber I9, after removal of the top I4 with its attached parts and the inner cylinder I'I, may be filled with a suitable gas generating solution, such as a saturated solution of sodium bicarbonate with or without a suitable foam stabilizing agent. Chamber I9 is only partially filled to allow room for insertion of the cylinder I'I. Cylinder I! may contain an acid reacting constituent, such as a solution of aluminum sulfate. The loaded cylinder I! with the cage 20 attached thereto is introduced into the fire extinguisher through the openings I2 and I6 to the position illustrated. Top member I4 with the rod 29 attached to the head 35 of the metering stopple is then screwed on to the top of the fire extinguisher and the hand wheel 30 is rotated to press the rubber disc 39 down securely against the top of the cage 20 adjacent the opening 4|. In this position, the cylinder I1 is sealed and reaction of the chemicals is prevented even though the fire extinguisher be turned upside down.

In operating the fire extinguisher to produce foam, the fire extinguisher is tilted at any suitable angle for the solutions to flow into the mixing chamber 42. The solution from storage chamber I9 is thus allowed to flow out into the mixing chamber 42 through the space between cylinder I I and the inner edge of partition I5. Hand wheel 39 is now rotated to move the rod 29 and the metering stopple to a position such that the washer 33 bears tightly against the inner side of the top member I4 and serves to prevent any leakage of gas or liquid around the rod 29. The opening of predetermined area between the skirt member 31 and the washer 49 is thus exposed so that the acid solution may flow from the storage space IB into the mixing chamber 42 through the opening. The metering stopple may, of course, be only partially withdrawn so that only a portion of the opening in the skirt is exposed for the flow of solution out of storage chamber I8. A fire extinguisher is thus provided in which the rate of chemical reaction and the range of force of foam ejection may be varied by adjusting the hand wheel 39, but in which the range and force of foam ejection may never exceed a fixed predetermined maximum even in the hands of an unskilled operator. I prefer to make the total area of the opening through which the carbonate solution fiows from chamber I9 into the mixing chamber 42 substantially larger or at least as large as the maximum opening that will be desired for passage of the acid solution from the chamber I3 into the mixing chamber 42. By simply varying the size of the washers M at the time the fire extinguisher is charged, the maximum possible rate of discharge of the fire extinguisher is controlled.

I have found that a fire extinguisher constructed in accordance with my invention without providing breather pipes or other special means for allowing gas to pass from the mixing chamber into the storage chambers other than the openings for passage of the solutions, produces a uniform non-pulsating discharge of foam from the hose 45. In fact, where a special breather pipe is provided extending from mixing chamber 42 to near the bottom of chamber I9,'noticeable pulsations of the foam stream are produced.

A further advantage of providing a pretermined maximum rate of discharge even when the extinguisher is used by a person who understands its operation is the greater speed with which the apparatus may be placed in operation without producing too forceful a discharge. Where a fixed maximum rate has been provided in advance, the handwheel 39 may be quickly rotated to the fully open position without danger of producing the foam too fast. If the operator is able to get closer to the fire after partial extinguishment thereof, the rate of chemical reaction may be suitably decreased by partially closing the metering stopple.

A modified form of metering stopple is illustrated in Figs. 4 and 5 whereby the operator is provided with a greater range of flexibility in varying the rate of reaction of the chemicals in the mixing chamber 42. In this form of metering stopple, the skirt member 49 has a solid end portion 50 and is clamped against the head 35 with the rubber disc or washer 39 therebetween by means of the bolts 5|. The skirt 49 is provided with a number of longitudinal slots 52 extending parallel to the major axis of the cylinder ll. In the operation of this form of metering stopple, the handwheel 30 may be adjusted to lift the skirt 49 any desired distance above the upper edge of the openings M. In this manner a greater or less portion of the total area of the slots 52 is exposed through which the acid solution may fiow from the storage chamber l8 into the mixing chamber 42. This form of metering stopple may be more desirable for use by an experienced operator or under conditions where a greater degree of flexibility of control is desired. The provision of longitudinal slots provides for uniform variation of the rate of chemical reaction and also for finer adjustments in this rate of reaction. If desired, the stopple skirt 49 may be used in testing the fire extinguisher to determine the setting or spacing that should be given to the skirt 3'! for use of the extinguisher in any given location, such as a boiler room, with the best results.

The terms and expressions which I have employed are used as terms of description and not of limitation, and I have no intention, in the use of such terms and expressions, of excluding any equivalents of the features shown and described or portions thereof, but recognize that various modifications are possible within the scope of the invention claimed.

I claim:

1. In a foam producing fire extinguisher comprising a pair of solution storage chambers, a mixing chamber and a partition separating said mixing chamber from one of said storage chambers and permitting only a restricted flow of solution to the mixing chamber, a metering stopple comprising a head for preventing the flow of solution from said other storage chamber to said mixing chamber, a cylindrical skirt member removably attached to Said head, means for spacing said skirt member from said head to provide an opening of predetermined size for the passage of solution, and means operable from outside the extinguisher for moving said head and skirt member to vary the amount of said opening exposed for the passage of solution.

2. A foam producing fire extinguisher comprising a pair of solution storage chambers, a mixing chamber, means for discharging foam from said mixing chamber, a partition separating one of said storage chambers from said mixing chamber having at least one opening for the passage of solution, such opening being the only means whereby gas may pass from said mixing chamber to said storage chamber, a meterin stopple comprising a head for preventing the flow of solution from said other storage chamber to said mixing chamber, a cylindrical skirt member attached to said head, means for spacing said skirt member from said head to provide an opening of any one of a number of predetermined sizes for the passage .of solution, and means operable from outside the extinguisher for moving said head and skirt member to vary the amount of said opening exposed for the passage of solution.

3. In a foam producing fire extinguisher comprising a pair of solution storage chambers, a mixing chamber, and a partition separating said mixing chamber from one of said storage chambers and permitting only a restricted flow of solution to the mixing chamber, a metering stopple comprising a head for preventing the flow of solution from said other storage chamber to said mixing chamber, a cylindrical skirt attached to said head extending into said other storage chamber and provided with longitudinal slots of substantially uniform width for metering the passage of solution, and means operable from outside the extinguisher to move said head and skirt so that variable portions of said slots are exposed for the passage of solution therethrough.

4. A fire extinguisher comprising a mixing chamber, a pair of solution storage chambers, and a metering stopple for controlling the flow of solution from one of said storage chambers into said mixing chamber, said metering stopple having a head portion adapted to prevent the flow of said solution into the mixing chamber, a skirt portion provided with a long narrow opening of substantially uniform width throughout its length through which said solution flows into the mixing chamber, and means operable from outside the extinguisher for moving said head and skirt portions to expose different portions of said opening and thereby control the proportion of said solution flowing into said mixing chamber.

5. A fire extinguisher comprising a mixing chamber, a pair of solution storage chambers, and a metering stopple for controlling the flow of solution from one of said storage chambers into said mixing chamber, said metering stopple having a head portion adapted to prevent, the flow of said solution into the mixing chamber, a skirt portion removably attached to said head portion with spacing means therebetween to provide an opening of predetermined size through which solution may flow into the mixing chamber, and means operable from outside the extinguisher to move said stopple from the closed to the open position.

GEORGE ENNIS FERGUSON. 

